Even though microchannel plates have been produced having a metallic coating deposited partially within each open end of the channels, there has been little success in depositing a secondary electron emissive metallic layer along the entire length of the interior walls of the channels. Generally, any partially secondary electron emissive layer, semiinsulating layer, etc., is formed on the interior walls of the channels by virtue of being built into the entire layer of the microchannel plate.
The present inventive process and apparatuses resulting therefrom pertains to a method of depositing either a thin film of nickel on the interior channel walls, or by prolonged deposition forming a solid layer of nickel to form a conductive panel. The process comprises securing a microchannel plate wafer in a heated deposition chamber and passing a mixture of inert gas and nickel compound gas through the channels to decompose the microchannel plate material and deposit a thin nickel layer on the inside walls of the channels, or by continuing the process over a larger period of time filling in the channels almost entirely to produce a conductive panel having a multiple of solid conductors. The temperature of the deposition chamber is thermostatically controlled and, after the inert gas is passed through the channels for about 40 minutes at 270.degree. Centigrade, the nickel compound gas is mixed with the inert gas and the gas mixture is passed therethrough at a lower temperature. A nickel compound, such as nickel carbonyl but not limited to this particular nickel compound, is heated in the nickel compound chamber and is valve released into the insulated piping between the inert gas chamber and the deposition chamber such that the mixture of inert gas and nickel carbonyl gas are thermostatically maintained at a temperature that is lower than the originally established 270.degree. Centigrade. The heated nickel carbonyl gas is passed through the channels in various runs at different times and temperatures. Generally, the 270.degree. Centigrade inert gas is passed through the wafer for about forty minutes and then the temperature of the heat element is lowered and the nickel carbonyl gas is passed through the wafer at a temperature of 150.degree. to 200.degree. Centigrade for times varying from 2 to 10 minutes.
Upon passing through the heated deposition chamber, the nickel carbonyl gas decomposes depositing nickel on the interior walls of the channels. After the wafer is removed from the deposition chamber the nickel coating on the walls of the channels may be further treated to enhance secondary electron emission by oxidizing the nickel surface or by forming metallic halides on the nickel surface.